1. Field of the Invention
The present invention relates to a rotary holder for a corrugated tube holding rotatably a corrugated tube in which a wire harness is received.
2. Description of the Related Art
A rotary holder for a corrugated tube as shown in FIGS. 1 to 5 has been known conventionally. A rotary holder device for a corrugated tube 1, as shown in FIGS. 1 to 2, is composed of an outer fixing body 2 and an inner rotary body 3 received rotatably in an inner portion of the outer fixing body 2. A corrugated tube 4 containing a wire harness W therein is held in an inner portion of the inner rotary body 3.
As shown in FIGS. 1 to 3, the outer fixing body 2 is formed by butting a butt surface 5b of a base member 5 against a butt surface 6b of a cover 6. An inner rotary chamber 8 surrounded by an inner sliding surface 7 is formed in an inner portion of the outer fixing body 2. Further, the inner sliding surface 7 is formed by a recessed arch surface 5a of the base member 5 and a recessed arch surface 6a of the cover 6.
Further, as shown in FIGS. 1 and 4, the inner rotary body 3 is composed of two semi-cylindrical divided rotary members 9, 9 each of which has a round arch surface on an outer periphery thereof. The inner rotary body 3 is formed by butting a butt surface 9b of one divided rotary member 9 against a butt surface 9b of the other divided rotary member 9. Further, a round outer peripheral sliding surface 10 is formed by assembling a round arch surface 9a of one divided rotary member 9 onto a round arch surface 9a of the other divided rotary member 9 without generating a step. The outer peripheral sliding surface 10 of the inner rotary body 3 moves sliding along the inner sliding surface 7 of the outer fixing body 2, whereby the inner rotary body 3 rotates in the inner portion of the outer fixing body 2. On the basis of the structure mentioned above, the corrugated tube 4 is rotatably held by the rotary holder for the corrugated tube 1.
However, since the outer fixing body 2 in the conventional rotary holder for the corrugated tube 1 is composed of the base member 5 and the cover 6 for the purpose of receiving the inner rotary body 3 in the inner portion thereof, it has been liable to occur that the butt surface 5b of the base member 5 may displace from the butt surface 6b of the cover 6 due to a failure of a lock means 11, 11 provided between the base member 5 and the cover 6, and due to an outward force applied to the base member 5 and the cover 6 as shown in FIG. 5. Once a displacement is generated between the butt surfaces 5b, 6b, a step portion is generated in a portion at which the recessed arch surface 6a of the cover 6 has been smoothly connected to the recessed arch surface 5a of the base member 5. Under this state, when the inner rotary body 3 rotates in the inner portion of the outer fixing body 2, a diameter of an inner sliding surface 7 of the outer fixing body 2 is substantially reduced at an amount of displacement d2. Therefore, the inner rotary body 3 can not smoothly rotate in the inner portion of the outer fixing body 2.
Further, in the case that the corrugated tube 4 receiving the wire harness W largely swings around the inner rotary body 3, the corrugated tube 4 is easily bent in an opening portion of the outer fixing body 2 for receiving the corrugated tube 4. In some cases, it has also been liable to occur that the corrugated tube 4 and a plurality of electric wires constituting the wire harness W are damaged.